纳米羟基磷灰石与聚己内酯复合电纺膜的制备及性能研究

发布时间：2018-06-28 13:57

本文选题：纳米羟基磷灰石 + 聚己内酯　；参考：《安徽大学》2012年硕士论文

【摘要】：生物支架材料一直都是组织工程领域研究的主要内容之一。几乎所有的具有可生物降解性,无论天然大分子和合成高分子生物材料均可用于不同组织工程支架研究。近年来,发展了如热致相分离法、致孔剂法、静电纺丝法等十余种组织工程的制备技术。其中,静电纺丝法由于能够直接制备连续的聚合物纳米纤维,因此有其独特的优势。电纺制备的纳米纤维支架结构类似于细胞间质,有利于细胞的粘附增殖。目前,电纺纤维支架材料已经广泛应用于各种组织工程的研究,尤其是骨组织工程方面。本文采用水热合成法,成功制备了尺寸为20-30nm×50-70nm的棒状nHA,并利用nHA活性粉体引发ε-CL单体聚合,成功合成了nHA含量不同的nHA-PCL复合材料。取nHA含量为5%的nHA-PCL-3作为样品,对nHA-PCL复合材料的电纺条件进行调试和选择。对于电纺溶剂的选择,主要研究了DCM和DMF体积比分别为1：1和2：1、DCM与甲酸体积比为1：1和2：1的四种混合溶剂。SEM结果显示：DCM和DMF的2种比例的混合溶剂电纺后得到的膜纤维交联严重、纤维无法独立呈现；而DCM和甲酸的混合溶剂电纺所得膜纤维的形貌好许多,尤其当体积比为2：1时的混合溶剂,膜纤维的粗细较均匀、纤维可以独立呈现；因而最终选择DCM和甲酸体积比为2：1的混合溶剂作为nHA-PCL复合材料的电纺溶剂。另外,在其他条件一致、单一因素改变的情况下,还对材料的不同的电纺浓度、电纺电压和接收距离进行实验。通过SEM图片看出,nHA-PCL复合材料的电纺浓度应控制在20%左右,适宜的电纺电压和接收距离分别为15kV和15cm。在选择合适的电纺条件后,成功制备出不同nHA含量的nHA-PCL的复合电纺膜,并对nHA-PCL复合电纺膜的结构和性能进行分析。SEM结果显示,电纺膜的纤维的直径随着nHA含量提高而降低；其中nHA含量为1%、3%和5%的复合电纺膜的纤维形貌较好,但含量为7%的nHA-PCL-4复合电纺膜,由于nHA颗粒的团聚,纤维粗细不均匀、连续性差、膜表面粗糙。从FT-IR和DSC的结果得到,电纺后的nHA-PCL复合材料较电纺前结品度有明显的提高,说明了nHA-PCL复合材料在强电力的拉伸作用下,分子链会沿着被拉伸方向取向,使得复合材料可以在纤维固化之前得到较充分的结品。此外,由于各nHA-PCL复合电纺膜的结品度的不同,表现在材料的力学性能也有所差异,其中当nHA含量为5%时的nHA-PCL-3复合电纺膜的力学性能最好,其拉伸强度和断裂伸长率分别为29.2±1.1MPa和55.6士1.5%。为研究nHA-PCL复合电纺膜的骨诱导性,将复合电纺膜放于1.5倍的SBF中浸泡,当浸泡7天后,各个电纺膜的纤维表面均有不同程度的沉积物形成；其中FT-IR结果显示,该沉积物主要成分为磷灰石,且随着nHA含量的提高,nHA-PCL电纺膜的磷灰石沉积量有所增加；另外,矿化后的复合电纺膜还表现在接触角比较矿化前有大幅度降低,说明矿化后的nHA-PCL电纺膜的亲水性良好。为了比较纯PCL和不同复合方式得到的nHA与PCL复合电纺材料的性能,对购买的纯PCL、物理共混nHA/PCL和化学接枝nHA-PCL的3种电纺膜进行研究。FT-IR、 DSC、SEM等的测试均表明了,含量均为5%的nHA在nHA-PCL中较nHA/PCL分散好,因此nHA在前者中异相成核点的作用较强,表现在前者的PCL结晶性能不仅高于后者,且还高于纯的PCL电纺膜；此外,nHA-PCL复合电纺膜的热稳定性及力学性能也明显高于另外两者。在1.5倍SBF仿生矿化实验结果显示,相同时间内nHA-PCL电纺膜纤维表面磷灰石的生成量明显高于nHA/PCL共混物电纺膜和纯PCL电纺膜,显示出良好的生物成骨性能。
[Abstract]:Biological scaffolds have been one of the main contents of the research in the field of tissue engineering. Almost all of them have biodegradability, both natural macromolecules and synthetic polymer biomaterials can be used in the study of different tissue engineering scaffolds. In recent years, more than ten kinds of tissues such as thermal phase separation, pore forming agent, electrospinning and so on have been developed. The electrostatic spinning method has its unique advantages because it can directly prepare the continuous polymer nanofibers. The structure of the nanofiber scaffold prepared by electrospinning is similar to the cell interstitium and is beneficial to the cell adhesion and proliferation. Especially in bone tissue engineering.
In this paper, a rod like nHA with a size of 20-30nm x 50-70nm was successfully prepared by hydrothermal synthesis. The nHA-PCL composite with different nHA content was successfully synthesized by using nHA active powder to induce the monomer -CL monomer polymerization. A nHA-PCL-3 of nHA content of 5% was taken as a sample, and the electrospun conditions of the nHA-PCL composite were tested and selected. The choice of DCM and DMF volume ratio of 1:1 and 2:1, DCM and formic acid volume ratio of 1:1 and 2:1 four kinds of mixed solvent.SEM results show that the 2 proportion of DCM and DMF mixed solvent electrospun is serious, fiber can not be independently presented; DCM and formic acid mixed solvent electrospun membrane fiber The morphology of the dimension is much better, especially when the volume ratio is 2:1, the thickness of the membrane fiber is more uniform and the fiber can be presented independently. Thus, the mixed solvent of DCM and the volume ratio of formic acid to 2:1 is selected as the electrospun solvent of the nHA-PCL composite. Different electrospun concentration, electrospun voltage and receiving distance are tested. Through SEM images, it is found that the electrospun concentration of nHA-PCL composites should be controlled at about 20%, and the suitable electrospun voltage and receiving distance are 15kV and 15cm., respectively.
After selecting suitable electrospinning conditions, the composite electrospun membranes with different nHA content of nHA-PCL were successfully prepared and the structure and properties of nHA-PCL composite electrospun membranes were analyzed..SEM results showed that the diameter of the fibers of the electrospun membranes decreased with the increase of nHA content, and the fiber morphology of the composite electrospun membranes with nHA content of 1%, 3% and 5% was better, but the morphology of the fiber was better. The nHA-PCL-4 composite electrospun membrane with a content of 7%, because of the agglomeration of nHA particles, the roughness of the fiber is not uniform, the continuity is poor, the surface of the membrane is rough. From the results of FT-IR and DSC, the nHA-PCL composite material after electrospun is obviously improved compared with the electrospinning. It shows that the molecular chain will be dragged along the tensile force of the strong electric power. In addition, the mechanical properties of the nHA-PCL composite electrospun membranes are different. In addition, the mechanical properties of the nHA-PCL-3 composite electrospun membranes with nHA content of 5% are the best, and the tensile strength and elongation at break are the best. The rate of 29.2 + 1.1MPa and 55.6 St 1.5%. was the bone inducibility of the nHA-PCL composite electrospun membrane. The composite electrospun membranes were soaked in 1.5 times of SBF, and the surface of the fibers of the electrospun membranes were formed in different degrees of sediment when they were soaked.
FT-IR results show that the main component of the deposit is apatite, and the amount of apatite in the nHA-PCL electrospun membrane increases with the increase of the content of nHA. In addition, the composite electrospun membrane after mineralization is also greatly reduced before the contact angle is mineralized, indicating that the hydrophilic property of the nHA-PCL electrospun membrane after mineralization is good.
In order to compare the properties of nHA and PCL composite electrospun materials obtained by pure PCL and different composite methods, 3 kinds of electrospun membranes purchased pure PCL, physical blending nHA/PCL and chemical grafting nHA-PCL were studied.FT-IR, DSC, SEM and other tests showed that nHA in the nHA-PCL 5% was better than nHA/PCL dispersed in nHA-PCL. The effect of the point is stronger than that of the former, which is not only higher than the latter, but also higher than the pure PCL electrospun membrane. In addition, the thermal stability and mechanical properties of the nHA-PCL composite electrospun membrane are obviously higher than that of the other two. The results of the 1.5 times SBF biomimetic mineralization experiment show that the formation of apatite on the surface of nHA-PCL electrospun fiber surface within the same time is at the same time. It is obviously higher than that of nHA/PCL blend electrospinning film and pure PCL electrospinning film, showing good biological osteogenic property.
【学位授予单位】：安徽大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

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